A number of printers, copiers, and multi-function products utilize heater chips in their printing heads for discharging ink drops from one or more ink vias. These heater chips typically provide only one heater array for each ink via that is disposed along one side of the ink via. In particular, as shown in FIG. 1, a traditional heater chip 100 may include three ink vias—a cyan ink via 102, a magenta ink via 104, and a yellow ink via 106. The cyan ink via 102 operates with the cyan heater array 108; the magenta ink via 104 operates with the magenta heater array 110; and the yellow ink via 106 operates with the yellow heater array 112. However, the traditional use of single heater array on a single side of an ink via limits the achievable printing resolution, including the vertical resolution. The configuration shown in FIG. 1 may have significant difficulty providing ink drop sizes of less than 4 pL (picoliters) while achieving a vertical resolution of about 1200 dpi (dots per inch) or better.
In addition, connections between the logic arrays and the heater arrays they address occupy a significant amount of space on the heater chips. In some instances, these connections may occupy as much space as the heater arrays themselves. As an example, as shown in FIG. 1, lengthy wiring buses 120, 122, and 124 have been utilized to allow communications between each of the P-register logic arrays 114, 116, and 118 and their respective heater arrays 108, 110, and 112. As shown in the configuration of FIG. 1, the wiring buses 120, 122, and 124 occupy significant space on the heater chip 100, thereby increasing the chip size and reducing the die yields per wafer.
Accordingly, there is a need in the industry for heater chips that can provide for enhanced printing resolutions while reducing chip die sizes.